Pipes are used as utility conduits for gases and liquids. Typically a large main pipe is placed under a paved street and smaller lateral pipes connect the main pipe to houses next to the street. These pipes can be for example stainless steel pipes for carrying natural gas to consumers. The pipes corrode and degrade over time creating tiny holes which leak gas. Therefore the pipes require maintenance or ultimately replacement. Gas pipes can be small in diameter. Typical lateral pipes can be about 20 to 30 mm in diameter which makes lining of the pipes impossible with inverting liners, a method known from sewer pipe rehabilitation. The pipes are also too small for spray coating or brush coating, methods also known from sewer pipe rehabilitation. Replacement of the pipes is also problematic since gas pipes are often in densely populated areas, under streets and buildings.
It is an object of the invention to present a method of reducing leaks in pipes which are difficult to access with tools.